Process for making corn chips



United States Patent PROCESS FOR MAKING CORN CHIPS Basil H. Kunce, JohnT. Long, Jr., and George G. Olson, Phoenix, Ariz., assignors to FiestaFoods Corporation, Phoenix, Ariz., a corporation of Arizona No Drawing.Application March 9, 1959 Serial No. 797,858

1 Claim. (Cl. 99-80) This invention pertains to an improved process formaking corn chips and is particularly directed to a process for makingcorn chips of crisp edible character.

One of the objects of this invention is to produce corn chips by aunique process by which they have a very low oil content and are only.060 of an inch thick (60 thousandths) while having a crunchy, flakytexture due to numerous small bubbles or blisters on the surface.

This is a continuation-in-part application of application Serial No.743,997, filed June 23, 1958.

Another object of this invention is to provide a new process thatutilizes a rolling and cutting technique to form the chip and a dryingor dehydration step prior to cooking in the shortening or cooking oil.

A further object of this process is to provide a chip with a much loweroil content in the finished product by dehydration of the corn doughprior to frying in oil so as to reduce the oil absorption by the chipfrom 25% to 35% over methods heretofore used.

Another object is to cut the dough prior to drying and frying so as topermit the corn chip to be made in a variety of sizes and shapes.

The new process also makes it practicable to produce a corn chip of thesame essential shape and thickness as a potato chip, a matter notheretofore possible.

And a still further object is to provide a process which gives carefulcontrol of a number of variables to produce the desired effects in theend product, over the established method of producing a corn chip, whichpermits a much wider variance in the degree to which the corn is cooked,the fineness of the grind and moisture content of the dough.

The present process used to produce this new and improved corn chip isas follows: Dry whole kernel yellow corn with a moisture content of to14% is placed in a suitable vessel and enough water added to just coverthe corn. The mixture is heated externally until a temperature of 170degrees is reached. The heat is then turned off immediately and themixture allowed to cool to room temperature. Care must be taken not toheat the corn to a temperature substantially above 170 degrees F. or theresulting dough will be too sticky to roll and cut to the desired shape.When the corn has cooled to room temperature it is washed and the excesswater allowed to drain off. The moist, cooked corn is then ground bysuitable means to a fineness such that 100% can be washed through a U.S.No. 20 screen and 75% can be washed through a US. No. 325 screen.

During grinding, the moisture content of the corn dough is adjusted toapproximately 50% to give the dough the proper consistency for workingthrough the ollers and cutters.

The dough is then worked between two oppositely rotating rollers againstone of which a rotating cutting bar is operating. The thickness of theresulting chip is determined by the spacing between the rollers which isheld to 14 thousandths of an inch. A wire held against one of therollers frees the cut dough from the roller and theformed chip fallsoff. the roller by' gravity onto a moving belt;

T he. dehydration. step which follows is unique to this process andessential to produce a corn chip with the above mentioned properties.The dough as it is: rolled and cut has amoisture. content of 50% and inthe-conventional. process-for preparing-corn. chipswould now be friedin. oil. In this process the-moisturecontent of the chip is reduced from5.0% to not more: than 20%. It has been found in practice that bestresults are obtained with a moisture content of 15%. The moisture con:-tent: should not be lower: than 10% orthe' resulting" chip will be toughand'ibrittleafter fry-ing. v a

The reason that the ordinary corn chips do not puff is that they arecoursely ground so that the dough is disconnected and steam frommoisture within the dough can readily escape from the chip during thefrying process. The chip of this invention is finely ground with asmooth, continuous surface. If fried with 50% water content, they wouldpuff because the moisture cannot readily escape. However, by reducingthe moisture to 15%, just enough remains to create the small blisterswhich give the chip the flaky, crisp yet tender texture.

In practice it has been found that a better product is made if themoisture is removed as rapidly as possible. A convenient procedure fordoing this uses a traveling metal slat belt moving through a gas firedoven. The oven is maintained at a temperature ranging from 675 degreesto 725 degrees F. and the corn chip is in the oven for a period of 30seconds. This rapid dehydration reduces the moisture content to 15% andthe chip is ready for frying. It has been observed with a rolled and cutchip that if the moisture content is above 20% the chips will putt whenthey are fried. The puffed chips do not cook evenly and the centercavity fills up with the cooking oil making an unpalatable product. Withextruded chips this difficulty is not noticed and does not present aproblem. With a moisture content of 15%, a chip with numerous smallsurface blisters is produced. The blisters add to the texture andflakeness of the product. The pre-baking, which drives out moisture alsoadds another desirable characteristic to the chip. In the production ofordinary corn chips, the moisture is replaced with oil which are fats.Laboratory tests of former chips show a fat content of 33.18% to 34.76%.Because the moisture in the instant chip is reduced to 15 prior totrying, the replacement is much less, and the instant chips have a fatcontent of 25.71%. This reduction in oil content also reduces thecalories. Other chips measure 2480 to 2554 calories per pound while theinstant chip measures 2200 to 2343 calories per pound. The reduction infat is great enough to make decided difference in the taste and otherorganoleptic characteristics. The instant chip has a drier, more daintyflavor, with no oily taste or feel that are predominant characteristicsof extruded chips that are not pre-baked, with a result, the consumercan eat far more of the instant chip with no undesirable after efiectsthat usually accompany the chips that are not pre-baked.

The chips are then fried in shortening corn oil or other vegetable oilsuntil a light golden brown. In practice, a refined corn oil has beenfound superior to other oils. The chips are fried in the oil for aperiod of from 25 to 40 seconds at a temperature of 370 degrees F.

The chips are then drained of excess oil, salted and packaged.

Having thus fully set forth and described this invention, what isclaimed is:

The process of making corn chips comprising the steps of: cooking yellowcorn having an initial moisture content of 10% in water by heating saidwater from room temperature to F., discontinuing said application ofheat immediately upon said water reaching 170 F. and allowing saidmixture to cool to room temperature, washing said thus cooked corn atsaid room temperature, and draining oil? the excess water, grinding themoist cooked corn to form a dough of a fineness such that 100% can bewashed through a U.S. No. 20 screen and 75% can be washed through a U.S.No. 325 screen and adjusting the moisture content thereof during saidgrinding to substantially 50%, kneading said dough between twooppositely rotated cylindrical rollers having their peripheral cylindricsurfaces spaced .014 apart, stripping said thus treated dough from saidrolls, cutting said rolled dough to desired chips, dehydrating saidchips from 50% down to a moisture content of 15%, said dehydration stepbeing undertaken in an oven ranging from 675 to 725 degrees F. for aperiod of 30 seconds, and

finally frying said dehydrated chips in shortening for a period of 30seconds at a temperature of 370 F. to produce a chip with numerous smallsurface blisters of good texture and fiakeness and of light golden brownwhen removed from and drained of said shortening ready for salting andpackaging.

References Cited in the file of this patent UNITED STATES PATENTS WynInc. (N.Y.), pp. 149, 186, 187.

